APSC 4464 EXAMINATION QUESTIONS WITH
ANSWERS
routes of enteral administration in food, in water or by oral gavage
routes of parenteral administration dermal/topical
inhalation
injections (IM, SQ, IV, IP, intracardiac, intranasal
steps of performing gavage in rodents? appropriate dose/volume ranges. measure from
corner of mouth to last rib for proper length/depth of insertion; restrain the animal; using
needle, push back on hard palate to rock head back so that passage is straight; ensure that
maximum recommended volume is not exceeded.
variables/concerns related to whole-body inhalation exposure besides behind inhaled,
also deposits on fur and skin, and can be ingested orally - thus greater dose than originally
calculated
variables/concerns related to nose-only inhalation exposure limits to just inhaled dose
describe why one might choose a luer-lock syringe over a standard syringe with thick
liquids, pressure may build when pushing plunger, and needle may shoot off. with a luer-lock
syringe, the needle is screwed on and won't fly off.
recognize the standard convention for identifying needle diameter (lower, number - greater
diameter, higher number - smaller diameter) and standard needle size ranges for the lab
animals discussed. lower # = larger gauge (diameter, 16g or 18g)
higher # = smaller gauge
(diameter, 25g or 27g)
standard needle sizes
rodents = 23 to 27 gauge
rabbits = 23 gauge
,why should needles not be reused? tissue trauma, contamination and pain
why are commercially manufactured (USP) drugs are better than non-pharmaceutical grade
agents? purity, sterility, acid-base balance, longer storage/shelf-life, absence of pyrogens
(produced by bacterial contaminants)
common injection sites in rodents? IM (thigh muscles of hind limbs) less than or equal to
0.05 ml for mice, less than or equal to 0.1 ml for hamsters, less than or equal to 0.3 ml for rats
SQ (over the back) less than or equal to 1 ml for mice, less than or equal to 2 ml for rats
IP (ventral abdomen - near midline upper portion of lower two quadrants) less than or equal to
1.5 ml for mice, less than or equal to 3 ml for rats
IV (lateral tail veins of rats & mice) less than or equal to 0.15 ml for mice, less than or equal to 1
ml for rats
common injection sites in rabbits? IM (thigh muscles for hind limbs; epaxial muscles
which parallel the spine) less than or equal to 0.5 ml
IP (same as in rodents)
SQ (same as in rodents)
IV (marginal ear vein)
what is important to remember for injections given in small animals? warm to near body
temperature to prevent hypothermia
recognize (in general) the ranges of safe blood collection volumes for the species discussed in
class mice = less than/equal to 0.3 ml
rat = less than/equal to
,3 ml
hamster = less than/equal to 1 ml
rabbit = less than/equal to 30 ml
recognize why the use of a vacutainers for blood collection in rodents may not be successful
? it has the potential to collapse the vessel, which can prevent the collection of blood
identify the location of the common vessels used for blood collection in the species discussed in
the species in class tail = lateral tail veins (rats & mice)
ear = marginal ear vein, central artery (rabbits)
face = submandibular & facial veins (rats & mice)
eye = retro-orbital sinus (rats, mice, rabbits)
front legs = cephalic vein (rabbits)
hind legs = lateral & medial saphenous veins (rats, mice, hamsters and gerbils)
metatarsal vein (gerbils & guinea pigs)
methods of promoting vasodilation to facilitate blood collection? warm the whole animal
or the area where blood will be collected. heating pad, heating lamps, warm water inside a
glove, dipping tail in warm water.
why is indwelling catheter maintenance is required, and steps to take to prevent thrombus
formation. to maintain sterility and prevent contamination; to prevent clot (thrombus)
formation; to prevent release of emboli.
after administration or blood collection, using a "heparin lock" solution to prevent clot
formation.
, describe proper "surgical scrub" procedures practiced at the site of the skin
incision. three alternating scrubs of betadine solution and alcohol.
start at the center, and spiral outward with scrub
describe the approach of a laparotomy? - clip site
- surgical scrub
- incise skin with a scalpel
- use rat-tooth forceps to handle skin and abdominal muscles
- cut along linea alba to open abdomen
describe the approach of a thoracotomy? - insert endotracheal tube
- clip site
- surgical scrub
- incise skin with scalpel
- use rat-tooth forceps to handle skin and intercostal muscles
- cut intercostal muscles (between ribs)
- loss of negative pressure in chest cavity results in collapse of the lungs
- manually inflate lungs or use a mechanical ventilator
why aren't scissors used to incise skin? they crush cells which in turn delay healing
why are rat-tooth forceps preferably used? they are less traumatic, less crushing of tissues
occurs
recognize and describe the appropriate use of several surgical instruments, and explain why
other instruments may be inappropriate for the same use (scalpel vs scissors; rat-toothed
forceps vs crushing forceps; hemostats skin and muscle: use rat-tooth forceps to prevent
excessive crushing of cells; use scalpel as cut cause less trauma to cells; scissors crush
cells/tissues, and for clamping off bleeding vessels.
what are swedged and non-swedged needles? why is one better than the other? swedged
needles have the suture contained within the end of the needle - does not stick out beyond
cross-section of needle, less drag, less trauma to tissues.
ANSWERS
routes of enteral administration in food, in water or by oral gavage
routes of parenteral administration dermal/topical
inhalation
injections (IM, SQ, IV, IP, intracardiac, intranasal
steps of performing gavage in rodents? appropriate dose/volume ranges. measure from
corner of mouth to last rib for proper length/depth of insertion; restrain the animal; using
needle, push back on hard palate to rock head back so that passage is straight; ensure that
maximum recommended volume is not exceeded.
variables/concerns related to whole-body inhalation exposure besides behind inhaled,
also deposits on fur and skin, and can be ingested orally - thus greater dose than originally
calculated
variables/concerns related to nose-only inhalation exposure limits to just inhaled dose
describe why one might choose a luer-lock syringe over a standard syringe with thick
liquids, pressure may build when pushing plunger, and needle may shoot off. with a luer-lock
syringe, the needle is screwed on and won't fly off.
recognize the standard convention for identifying needle diameter (lower, number - greater
diameter, higher number - smaller diameter) and standard needle size ranges for the lab
animals discussed. lower # = larger gauge (diameter, 16g or 18g)
higher # = smaller gauge
(diameter, 25g or 27g)
standard needle sizes
rodents = 23 to 27 gauge
rabbits = 23 gauge
,why should needles not be reused? tissue trauma, contamination and pain
why are commercially manufactured (USP) drugs are better than non-pharmaceutical grade
agents? purity, sterility, acid-base balance, longer storage/shelf-life, absence of pyrogens
(produced by bacterial contaminants)
common injection sites in rodents? IM (thigh muscles of hind limbs) less than or equal to
0.05 ml for mice, less than or equal to 0.1 ml for hamsters, less than or equal to 0.3 ml for rats
SQ (over the back) less than or equal to 1 ml for mice, less than or equal to 2 ml for rats
IP (ventral abdomen - near midline upper portion of lower two quadrants) less than or equal to
1.5 ml for mice, less than or equal to 3 ml for rats
IV (lateral tail veins of rats & mice) less than or equal to 0.15 ml for mice, less than or equal to 1
ml for rats
common injection sites in rabbits? IM (thigh muscles for hind limbs; epaxial muscles
which parallel the spine) less than or equal to 0.5 ml
IP (same as in rodents)
SQ (same as in rodents)
IV (marginal ear vein)
what is important to remember for injections given in small animals? warm to near body
temperature to prevent hypothermia
recognize (in general) the ranges of safe blood collection volumes for the species discussed in
class mice = less than/equal to 0.3 ml
rat = less than/equal to
,3 ml
hamster = less than/equal to 1 ml
rabbit = less than/equal to 30 ml
recognize why the use of a vacutainers for blood collection in rodents may not be successful
? it has the potential to collapse the vessel, which can prevent the collection of blood
identify the location of the common vessels used for blood collection in the species discussed in
the species in class tail = lateral tail veins (rats & mice)
ear = marginal ear vein, central artery (rabbits)
face = submandibular & facial veins (rats & mice)
eye = retro-orbital sinus (rats, mice, rabbits)
front legs = cephalic vein (rabbits)
hind legs = lateral & medial saphenous veins (rats, mice, hamsters and gerbils)
metatarsal vein (gerbils & guinea pigs)
methods of promoting vasodilation to facilitate blood collection? warm the whole animal
or the area where blood will be collected. heating pad, heating lamps, warm water inside a
glove, dipping tail in warm water.
why is indwelling catheter maintenance is required, and steps to take to prevent thrombus
formation. to maintain sterility and prevent contamination; to prevent clot (thrombus)
formation; to prevent release of emboli.
after administration or blood collection, using a "heparin lock" solution to prevent clot
formation.
, describe proper "surgical scrub" procedures practiced at the site of the skin
incision. three alternating scrubs of betadine solution and alcohol.
start at the center, and spiral outward with scrub
describe the approach of a laparotomy? - clip site
- surgical scrub
- incise skin with a scalpel
- use rat-tooth forceps to handle skin and abdominal muscles
- cut along linea alba to open abdomen
describe the approach of a thoracotomy? - insert endotracheal tube
- clip site
- surgical scrub
- incise skin with scalpel
- use rat-tooth forceps to handle skin and intercostal muscles
- cut intercostal muscles (between ribs)
- loss of negative pressure in chest cavity results in collapse of the lungs
- manually inflate lungs or use a mechanical ventilator
why aren't scissors used to incise skin? they crush cells which in turn delay healing
why are rat-tooth forceps preferably used? they are less traumatic, less crushing of tissues
occurs
recognize and describe the appropriate use of several surgical instruments, and explain why
other instruments may be inappropriate for the same use (scalpel vs scissors; rat-toothed
forceps vs crushing forceps; hemostats skin and muscle: use rat-tooth forceps to prevent
excessive crushing of cells; use scalpel as cut cause less trauma to cells; scissors crush
cells/tissues, and for clamping off bleeding vessels.
what are swedged and non-swedged needles? why is one better than the other? swedged
needles have the suture contained within the end of the needle - does not stick out beyond
cross-section of needle, less drag, less trauma to tissues.
